The morphological and biochemical analysis of hair roots and skin will be used as a sensitive criteria for the diagnosis of protein malnutrition in rats and monkeys with experimental protein malnutrition. The morphological techniques to be used in examining hairs include the anagen/telogen ratio, the hairs with present root sheaths, the diameter of the hair bulb, the amount of DNA and protein in the hair bulb, quantitative and qualitative differences in the high and low sulfur containing structural proteins of the hair bulbs, and the activity of various enzyme in the hair bulbs and skin. The in vitro synthesis of protein and nucleic acids will be measured in the hair bulbs as well. Ornithine decarboxylase the rate limiting enzyme in polyamine synthesis is being studied in human and rodent skin. The hair abnormality in Menkes disease is being defined in terms of alterations in the extractability of the structural proteins, and their qualitative and quantitative nature.